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    SubjectRe: [git] CFS-devel, updates
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    On Sun, 2007-09-23 at 13:58 +0200, Ingo Molnar wrote:

    > i'm also wondering - do we even need sync_vruntime() at all? Now that we
    > fix up vruntime while we migrate tasks across rqs, the global notion of
    > vruntime makes less and less of a sense.

    Yeah, I was wondering that too, but it does seem to be needed. If I
    make it a noop, and run the pinned tasks with an unpinned make -j2 test,
    Xorg at nice -5 still takes hits...

    se.wait_max : 11.513462
    se.wait_max : 6.250911
    se.wait_max : 15.181511
    se.wait_max : 188.963625
    se.wait_max : 4.951569
    se.wait_max : 11.391749

    ...which begs the question "gee, what happens if I pin a nice 0 hog to
    CPU0, and a nice 19 hog to CPU1 with the queues never ever syncing?".

    The answer to that one seems to be "Don't even think about it!". This
    needs more investigation... there's gotta be a 32 bit thingie hiding in
    there. I lost control for a few seconds, got it back, then lost it
    again forever (sysrq-b worked though, hmm).

    -Mike

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